Biology Exam 4

Opisthokonts

a major eukaryotic clade that includes Animals,Fungi,Protists like choanoflagellates

Fungi evolved from

Aquatic, unicellular, flagellated protists

Synapomorphies shared by all Fungi

• Chitin cell walls

• Absorptive heterotrophy

• Hyphae → mycelium body structure

• Spores for reproduction

Body Form of Fungi

hyphae (filaments), mycelium network

Ecological Role of Fungi

Major Decomposers

Nutrition of Fungi

Saprophytes (decomposers), Parasites, and Mutualists

Chytridiomycota

Zoospores, only fungi with flagella

Mucoromycota

Sporangia / zygosporangia, Bread Molds

Zoopagomycota

Sporangia, Parasites of animals/protists

Ascomycota

Asci (sacs) + conidia, Yeasts and Molds

Basidiomycota

Basidia, Mushrooms

Animal Morphology

Choanoflagellates ≈ sponge choanocytes

Animal Genetics

Shared genes for cell adhesion and signaling

Animal behavior

form colonies and step toward multicellularity

Choanoflagellates

closest relatives to animals

Synapomorphies shared between aniamls

multicellularity, no cell walls, ingestive heterotrophy, and nerve and muscle cells

Radial

the organism can be divided into equal halves from multiple planes

biateral

can be divided into two equal halves (left and right) along one plane only

acoelomate

an animal that does NOT have a body cavity

pseudocoelomate

an animal with a body cavity (pseudocoel) that is NOT completely lined by mesoderm

coelomate

an animal with a true coelom, meaning a fluid-filled body cavity completely lined by mesoderm

Proteosome

• Arthropods (insects, spiders)

• Mollusks (snails, clams)

  • Annelids (earthworms)

Deuterostomes

• Echinoderms (sea stars)

  • Chordates (humans, vertebrates)

PROTO

first mouth

DEUTERO

second mouth (anus first, mouth second)

Porifera

• Symmetry: asymmetrical

• Tissues: none (no true tissues)

• Body cavity: none

• Key traits: pores, choanocytes, filter feeders

Cnidaria

• Symmetry: radial

• Tissues: true tissues

• Body cavity: none (gastrovascular cavity)

• Key traits: cnidocytes (stinging cells), 2 tissue layers

Platyhelminthes

• Symmetry: bilateral

• Body cavity: acoelomate

• Key traits: flat body, simple organs, some parasites

Nematoda

• Symmetry: bilateral

• Body cavity: pseudocoelomate

• Key traits: complete digestive system, many parasites

Annelida

• Symmetry: bilateral

• Body cavity: coelomate

• Key traits: segmentation, closed circulatory system

Mollusca

• Symmetry: bilateral

• Body cavity: coelomate

• Key traits: mantle, foot, visceral mass, often shell

Arthropoda

• Symmetry: bilateral

• Body cavity: coelomate

• Key traits: exoskeleton, jointed appendages, segmentation

• Most diverse group on Earth

Echinodermata

• Symmetry: radial (adults), bilateral (larvae)

• Body cavity: coelomate

• Key traits: water vascular system, tube feet

Chordata

• Symmetry: bilateral

• Body cavity: coelomate

Cephalochordata

Invertebrate

Urochordata

Invertebrate

Vertebrata

Vertebrate

~95–97% of animals

Invertebrates

~3–5%

Vertabrates

Arthropods

most diverse organisms on Earth

Vertebrates

animals within the phylum Chordata that have a backbone and a cranium(Skull)

Invertebrates

animals that do NOT have a backbone (vertebral column)

diploblastic

animals that develop from two primary germ layers during embryonic development

Ectoderm

outer layer

Endoderm

inner layer

triploblastic

animals develop from three primary germ layers during embryonic development

Mesoderm

muscles, bones, organs, circulatory system

Parazoa

group of animals that lack true tissues and organs

Eumetazoa

animals that have true tissues